Biomarker responses by crucian carp (Carassius carassius) living in a pond of secondary treated pulp mill effluent

The hormonal effects of treated pulp mill effluent on sexually mature crucian carp (Carassius carassius) living in a wastewater pond of the Enocell bleached sulphate pulp mill, Finland, were investigated. The effluent running into the pond had been treated in an activated sludge unit. Concentrations of chlorophenols, chloroguaiacols, chlorocathecols, chloroveratrols, resin acids and beta -sitosterol were determined in fish bile and sediment. Fish length, weight, height, liver somatic index (LSI), gonad somatic index (GSI) and haemoglobin, haematocrit, testosterone, triiodothyronine (T3) and thyroxin concentrations were determined. The fish had elevated concentrations of chlorophenolics, resin acids and beta -sitosterol in bile compared with fish from a reference site. These compounds were also found in sediment of the wastewater pond. Exposed male fish had higher LSI and T3 concentrations and lower GSI, haemoglobin and haemocrit than reference fish. No vitellogenin production was observed in exposed male fish. Some female fish had decreased vitellogenin levels.